Plagiarism is presenting someone else's work as your own. It can include copying and pasting text from a website into a project you're working on, or taking an idea from a book without including a citation to give credit to its author. Plagiarism is common, and the Internet has made it even more common. However, if you are careful to cite your sources it's not too difficult to avoid plagiarism.

The way you cite your sources will vary depending on how formal you need to be. For example, if you're writing a blog article it's often enough to simply link to the original source. You may also want to mention the original author's name and/or the name of the website to help your readers tell at a glance where you're getting your information.

If you're writing a more formal paper, you will generally need to use a specific format for citations. You can use a style guide such as the Chicago Manual of Style to give your citations a consistent style. For these types of citations, you may list the sources as footnotes or include a bibliography at the end (or both).

Plagiarism in general english means “Illegal form of copying”. It could be a blog post, an image, a person photo or anything.